The invention relates to a thin-film magnetic head including a magnetoresistive element and a face for magnetically coupling the magnetoresistive element with a magnetic recording medium. A first layer and a coplanar second layer both consist of a magnetically permeable material, a gap bridged by the magnetoresistive element being present between the layers. The first layer has an end remote from the magnetoresistive element and adjoining the face. A third layer of a magnetically permeable material located on a side of the magnetoresistive element remote from the first and second layers extends from the face and is magnetically connected to the second layer.
A magnetic head of this type is illustrated in U.S. Pat. No. 4,489,357, herein incorporated by reference, which is particularly, but not exclusively intended for detecting magnetic fields of magnetic recording media such as magnetic tape or discs.
Magnetic heads of the type described above have an elongated resistive element. The magnetoresistive element may be magnetically biased, whilst for linearizing the reproducing characteristic of the magnetoresistive element it is necessary to apply a static magnetic field in order to displace the working point to a linear region of the resistance-magnetic field curve.
A magnetically biased magnetoresistive element is described, for example in European Patent Application 0,063,397, to which U.S. application No. 314,149 corresponds herein incorporated by reference. The magnetoresistive element may alternatively be a current-biased resistive element in which one or more oblique strips conducting in an electrically satisfactory manner are provided on one of the surfaces of the magnetoresistive element atan angle of approximately 45.degree. to the longitudinal axis of the element. The conducting strips function as equipotential strips in order that the direction of the current in the element, which is perpendicular to the equipotential strips, also extends at an angle of approximately 45.degree. to the easy axis of magnetization so that the transducing characteristic is linearized. A current-biased magnetoresistive element is described, for example in U.S. Pat. No. 4,425,593, herein incorporated by reference.
The known thin-film magnetic head has the drawback that during operation a relatively large amount of magnetic flux is lost between the flux-conducting layers of a magnetically permeable material located on the recording medium side of the magnetoresistive element, which loss results in a low efficiency of the known magnetic head.